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Abstract:

The invention relates to a method for loading containers (3, 4)
comprising at least one first empty housing (31, 41) and one second empty
housing (32, 42) the mentioned containers (3, 4) being intermittently
shiftable between a first rest position (1) and a second rest position
(1). The method comprises calculating an available time td corresponding
to the time necessary for an empty housing (31, 32, 41, 42) to reach a
loading position (11, 12, 21, 22), and comparing it with a positioning
time tp11, tp12, tp21 and tp22 necessary for the manipulator to collect
from its current position each object to be loaded from a collecting area
(5) and depositing it in a loading position (11, 12, 21, 22) coinciding
with the position of an empty housing (31, 32) (41, 42) of a container
(3, 4). The object to be collected (a, b, c, d) and the delivery position
of said object in an empty housing (31, 32) (41, 42) corresponds with a
loading position (11, 12, 21, 22) of the manipulator the positioning time
tp11, tp12, tp21 or tp22 of which is closest to the available time td.

Claims:

1. Method for loading containers (3, 4) comprising at least one first
empty housing (31, 41) and one second empty housing (32, 42) configured
to receive an object to be loaded, the mentioned containers (3, 4) being
intermittently shiftable by shifting means such that the containers (3,
4) can occupy a first rest position (1), during a rest time tr, and can
be shifted, during an advance time ta, from the first rest position (1)
to at least one second rest position (2), said shifting of the containers
(3, 4) being performed with a variable velocity throughout the advance
time ta, the loading of the object to be loaded being performed by means
of at least one manipulator which can collect the object to be loaded
from a collecting area (5) comprising at least one object (a, b, c, d)
and deliver it in a loading position (11, 12, 21, 22) coinciding with one
of the empty housings (31, 32) (41, 42) of one of the containers (3, 4)
characterized in that it comprises the following phases: Calculating an
available time td corresponding to the time necessary for an empty
housing (31, 32, 41, 42) of a container (3, 4) to reach a loading
position (11, 12, 21, 22), Calculating for each of the mentioned at least
one object (a, b, c, d): a positioning time tp11 necessary for the
manipulator to reach a first loading position (11) coinciding with the
position of a first empty housing (31, 41) of a container (3, 4), a
positioning time tp12 necessary for the manipulator to reach a second
loading position (12) coinciding with the position of a second empty
housing (32, 42) of a container (3, 4), a positioning time tp21 necessary
for the manipulator to reach a third loading position (21) coinciding
with the position of a first empty housing (31, 41) of a container (3,
4), a positioning time tp22 necessary for the manipulator to reach a
fourth loading position (22) coinciding with the position of a second
empty housing (32, 42) of a container (3, 4), Comparing the available
time td with the positioning times tp11, tp12, tp21 and tp22 of each of
the at least one object (a, b, c, d) in each of the loading positions
(11, 12, 21, 22) to determine a loading position (11, 12, 21, 22) of the
manipulator and an object to be loaded (a, b, c, d) the positioning time
tp11, tp12, tp21 or tp22 of which is closest to the available time td,
delivering said object (a, b, c, d) in said loading position (11, 12, 21,
22).

2. Method according to claim 1, according to which the manipulator shifts
from the collecting position to the loading position following a
rectilinear path.

3. Method according to, claim 1 wherein the loading position (11, 12, 21,
22) coincide with the position of an empty housing (31, 32, 41, 42) of a
container in a rest position (1, 2).

4. Method according to claim 3, wherein the available time td and the
positioning times tp11, tp12, tp21 and tp22 are calculated from the
detection of the start of the movement of the containers (3, 4) between
the first rest position (1) and the at least one second rest position
(2).

5. Loading method according to claim 3, wherein the available time td is
calculated as the sum of the advance time ta and a remaining time
trem so that the movement of the containers (3, 4) starts between
the first rest position (1) and the at least one second rest position
(2).

6. Loading method according to claim 5, wherein when the remaining time
trem is greater than any of the positioning times tp11, tp12, tp21,
tp22, the object to be collected and the delivery position corresponding
to the positioning time tp11, tp12, tp21, tp22 which is closest to the
remaining time trem are determined.

7. Loading method according to claim 1, wherein the loading position (11,
12, 21, 22) corresponds to a position of an empty housing (31, 32, 41,
42) between the first rest position (1) and the second rest position (2).

8. Method according to claim 7, wherein the available time td is
calculated as the sum of the advance time ta and a remaining time
trem so that the movement of the containers (3, 4) starts between
the first rest position (1) and the at least one second rest position
(2), the available time td being greater than the positioning times tp11,
tp12, tp21 and tp22 and the remaining time trem less than the
positioning time tp11, tp12, tp21, tp22.

9. Method according to claim 8, wherein the manipulator delivers the at
least one object (a, b, c, d) in the loading position (11, 12, 21, 22)
with a substantially nil relative velocity with respect to the container
(3, 4) and a shifting direction substantially parallel to the advance
direction of the container (3, 4).

10. Method according to claim 1 which comprises tracking the path of the
housings (31, 32, 41 and 42) when the positioning time tp11, tp12, tp21
and tp22 is less than the available time td.

11. Loading method according to claim 10, wherein the tracking of the
path comprises a first shifting of the manipulator which consists of
shifting in a straight line to a position close to the housing (31, 32,
41, 42) and a second shifting of the manipulator which consists of
tracking the position of the housing (31, 32, 41, 42).

12. Loading method according to, claim 1 wherein the collecting area (5)
is comprised within a work area (6) of the mentioned at least one
manipulator.

13. Packaging machine comprising shifting means which can intermittently
shift containers (3, 4) such that the containers (3, 4) can occupy a
first rest position (1), during a rest time tr, and can be shifted,
during an advance time ta, from the first rest position (1) to at least
one second rest position (2), said shifting of the containers (3, 4)
being performed with a variable velocity throughout the advance time ta,
comprising the containers (3, 4) at least one first housing (31, 41) and
one second housing (32, 42) configured to receive an object to be loaded
(a, b, c, d), the mentioned machine comprising at least one manipulator
which can collect an object to be loaded (a, b, c, d) from a collecting
area comprising at least one object (a, b, c, d) and deliver it in one of
the housings (31, 32, 41, 42) of one of the containers (1, 2),
characterized in that it comprises a control system and means of
communication between the shifting means and the at least one
manipulator, configured such that the at least one object to be loaded
(a, b, c, d) is deposited in one of the empty housings (31, 32, 41, 42)
according to a loading method according to any of the previous claims.

Description:

FIELD OF THE INVENTION

[0001] The present invention is comprised within the field of the devices
and methods for loading products in containers or receptacles which are
shifted moved by shifting means and, more specifically, intermittently
advancing containers in which the products are loaded by means of
manipulators.

BACKGROUND OF THE INVENTION

[0002] In many packaging processes the movement of the containers
throughout the installation is performed intermittently due to the
transformation processes (such as, for example, forming or sealing) which
the receptacle experiences in the different stations or machines. This
intermittent movement makes it difficult to efficiently load the products
in the receptacles or containers since once the loading movement starts,
the receptacle or container cannot advance until the loading has
completed, causing idle time in the packaging process.

[0003] The products to be loaded generally arrive by a conveyor belt
parallel to the loading station of the machine, in which it is
increasingly more common to find robots loading the product in the
housings of the container or receptacle. These robots grab a product or a
group of products from said belts and deliver it in the housings of the
previously formed container or receptacle. It is also common for the
products to advance in the direction opposite to the advance of the
receptacles (counter flow), although installations are also known in
which the products advance in the same advance direction of the
receptacles.

[0004] Currently, loading is performed with the container or receptacle
stopped (in the pauses of the intermittent movement during which the
forming, filling, sealing, cutting and extraction operations, among
others, are performed in the subsequent parts of the machine) and the
receptacle or container can comprise several housings which must be
filled during the mentioned pause in the advance of the container. Thus,
for example, if the receptacle to be filled has four housings and the
manipulator has only been able to fill 3 of the 4 housings in the current
cycle (pause of the intermittent movement) but has not had time to fill
the fourth housing, the machine must delay its advance until the robot
delivers the last product in the corresponding housing (for example in
the fourth housing). This delay in the advance reduces productivity of
the machine due to the accumulation of delay times.

[0005] To prevent these delays or idle times, there are alternatives based
on the robot following the receptacle during its advance.

[0006] A solution to this problem consists of preventing the machine from
remaining stopped until all the products have been loaded in their
housings, making the manipulator move, following the housing to be filled
during the advance of the machine and performing the loading with the
moving receptacle. This is very common in continuous processes, for
example, in the automotion sector.

[0007] However, in certain machines of the packaging sector, such as, for
example, the thermoforming machines, no transformation conferring an
added value to the receptacle/product is performed during the advance of
the receptacles, therefore shifting from one station of the machine to
another should be done as quickly as possible in order to eliminate these
idle times. To that end, in these cases the advance speeds of the
machine, and therefore of the receptacles, follow a very marked
acceleration-deceleration curve. In this case the course taken by the
robot while it follows a housing of the moving receptacle to deposit the
product is very long since the robot will change its direction vector as
it detects point-to-point the new positions of the housing. As a result,
the manipulator will follow a curved path, seen in plan view, which means
greater time and space traveled to reach the housing in which it will
finally deposit the product, the case in which the robot reaches the
housing once the advance has ended, or even later in very fast machines,
possibly occurring. Therefore, in this case the course of the robot is
not optimized and the excess time involves a reduction of the
productivity of the robot.

[0008] The present invention seeks to optimize the productivity of the
machine and to also optimize the excess time used by the robot to
increase its productivity.

DESCRIPTION OF THE INVENTION

[0009] An object of the invention is a method for loading containers
comprising at least one first empty housing and one second empty housing
configured to receive an object to be loaded, the mentioned containers
being intermittently shiftable by shifting means such that the containers
can occupy a first rest position, during a rest time tr, and can be
shifted, during an advance time ta, from the first rest position to at
least one second rest position. The shifting of the containers is
performed with a variable velocity (velocity with a non-constant
acceleration) throughout the advance time ta. The loading of the object
is performed by means of at least one manipulator (for example a robot)
which can collect the object to be loaded from a collecting area,
comprising at least one object, and deliver it in a loading position
coinciding with one of the empty housings of one of the containers. A
collecting area is a position within the work area of the manipulator in
which the object or the objects which are collected for subsequent
loading are located. The objects to be collected can be, for example in a
product warehouse, or on a conveyor belt shifting the objects at a
certain velocity. A loading position is a position which is within the
work area of the manipulator and in which the delivery of products is
provided, the manipulator being able to reach, for example, four
different loading positions (first, second, third and fourth loading
position) and these loading positions spatially coincide with the
location of one of the empty housings of one of the containers, such that
the loading of the manipulator in a loading position causes the product
to be loaded in a housing of a receptacle.

[0010] The method of the invention comprises the following phases:

[0011] Calculating an available time td corresponding to the time
necessary for an empty housing of a container to reach a loading
position,

[0012] Calculating for each of the mentioned at least one object
(comprised in the collecting area at the time of collection):

[0013] a positioning time tp11 necessary for the manipulator to reach a
first loading position coinciding with the position of a first empty
housing of a container,

[0014] a positioning time tp12 necessary for the manipulator to reach a
second loading position coinciding with the position of a second empty
housing of a container,

[0015] a positioning time tp21 necessary for the manipulator to reach a
third loading position coinciding with the position of a first empty
housing of a container,

[0016] a positioning time tp22 necessary for the manipulator to reach a
fourth loading position coinciding with the position of a second empty
housing of a container.

[0017] Then the available time td is compared with the positioning times
tp11, tp12, tp21 and tp22 of each of the at least one object (a, b, c, d)
in each of the loading positions (11, 12, 21, 22) to determine an object
to be collected and a loading position the positioning time tp11, tp12,
tp21 or tp22 of which is closest to the available time td.

[0018] Finally, the manipulator delivers said object in said collecting
position (after collecting the object from the collecting position).

[0019] According to the method of the invention, the movement of the
containers between a first rest position and a second rest position, and
more specifically, the time necessary for the empty housings of the
containers to reach a loading position, are taken into account. Based on
this data it calculates and decides which object is going to be collected
(in the event that there is more than one object in the collecting area)
and in which loading position the manipulator will deliver the object,
which loading position will obviously coincide with an empty housing of a
container.

[0020] To that end, the positioning times tp11, tp12, tp21 and tp22 of
each object (the time the manipulator needs in the current position to
collect each of the objects comprised in the collecting area and take
them to each empty housing in the pre-established possible loading
positions) are calculated and these times are compared with the available
time td (the time necessary for the empty housing of the container to
reach a loading position). Out of the possible objects to be collected
and the possible loading positions in which to deposit the objects, one
object will be chosen and it will be deposited in a loading position
having a positioning time which is closest to the available time. In
other words, the manipulator will collect an object and load it in a
loading position based on which of all the positioning times tp11, tp12,
tp21 and tp22 calculated for each object and for each of the loading
positions is closest to the available time td. This calculation is
constantly performed such that the manipulator chooses the objects to be
collected and loads said objects, always optimizing the necessary
positioning time, instead of maintaining a pre-established sequence when
collecting the objects to be loaded, or a pre-established loading order
in a loading position without taking into account mismatching between the
positioning time of the manipulator and the movement of the container.

[0021] The manipulator can shift from the collecting position to the
loading position following a rectilinear path, seen from above, to
minimize positioning times.

[0022] The first, second, third and fourth loading positions can coincide
with the position of an empty housing of a container in the first or
second rest position, such that the loading of the products is performed
when the containers are at rest, or they can coincide with positions
intermediate between the first and second rest position, such that the
loading is performed during the advance of the containers.

[0023] The method of the invention can comprise tracking the path of the
housings when there is a certain phase difference between the loading
position (theoretical) and the position of the empty housings, or when
the positioning times tp11, tp12, tp21 and tp22 are less than the
available time td, i.e., in these conditions the method of invention
would comprise tracking the housings. This tracking of the path can
comprise a first shifting of the manipulator consisting of shifting in a
straight line, seen in plan view, to a position close to the housing and
a second shifting of the manipulator consisting of tracking the position
of the housing. In the cases that the product is deposited in a housing
of a container that is still moving, the manipulator adapts its velocity
and direction to those of the container at the time of the delivery.

[0024] Another object of the invention is a packaging machine comprising
shifting means which can intermittently shift containers such that the
containers can occupy a first rest position, during a rest time tr, and
can be shifted, during an advance time ta, from the first rest position
to at least one second rest position, said shifting of the containers
being performed with a variable velocity throughout the advance time ta.
The containers comprise at least one first housing and one second housing
configured to receive an object to be loaded, the mentioned machine
comprising at least one manipulator which can collect an object to be
loaded from a collecting area comprising at least one object, and deliver
it in one of the housings of one of the containers. The machine
furthermore comprises a control system and means of communication between
the shifting means and the at least one manipulator, configured such that
the at least one object to be loaded is deposited in one of the empty
housings according to a loading method according to any of the previous
claims.

[0026] To complement the description being made and for the purpose of
aiding to better understand the features of the invention according to a
preferred practical embodiment thereof, a set of drawings is attached as
an integral part of said description in which the following is depicted
with an illustrative and non-limiting character:

[0027] FIG. 1 shows a schematic depiction of two containers (3, 4)
comprising empty housings (31, 32) (41, 42), container (4) being in the
first rest position (1) and housings (41 and 42) coinciding with loading
positions (11, 12) of the manipulator.

[0028] FIG. 2 shows a schematic depiction similar to that of FIG. 1 in
which containers (3) and (4) have advanced, container (3) being in the
first rest position (1) and container (4) in the second rest position
(2). In this situation, housings (31 and 32) coincide with loading
positions (11 and 12) and housings (41, 42) coincide with loading
positions (21, 22).

PREFERRED EMBODIMENT OF THE INVENTION

[0029] According to an embodiment shown in FIGS. 1 and 2, the method of
the invention allows loading products (a, b, c, d) in empty housings (31,
41, 32, 42) of containers (3, 4). The mentioned containers (3, 4) are
shifted intermittently by shifting means such that the containers (3, 4)
can occupy a first rest position (1), during a rest time tr, and can be
shifted, during an advance time ta, from the first rest position (1) to
at least one second rest position (2). The shifting of the containers (3,
4) is performed with a variable velocity throughout the advance time ta,
the loading of the object (a, b, c, d) being performed by means of at
least one manipulator which can collect the object to be loaded from a
collecting area (5) comprising at least one object (a, b, c, d), and
deliver it in a loading position (11, 12, 21, 22) coinciding with one of
the empty housings (31, 32) (41, 42) of one of the containers (3, 4). The
collecting area is comprised within the work area (6) of the manipulator
or manipulators. The loading positions (11, 12, 21, 22) can coincide with
the position of the empty housings (31, 32, 41, 42) in the first rest
position (1) and in the second rest position (2) as shown in FIGS. 1 and
2, or they can be located at an intermediate point between the first and
the second rest position (1, 2) where the housings (31, 32, 41, 42) of
the containers (3, 4) are shifted during the advance of the machine. In a
preferred and non-excluding embodiment of the present invention, a
collecting area comprising a conveyor belt (5) on which objects to be
collected (a, b, c, d) move at a constant velocity and in a direction
opposite to the advance of the machine is shown. One or more objects (d)
on said conveyor belt (5) can be found outside the work area of the
manipulator, as seen in FIG. 1. However, said objects (d) initially
located outside the work area of the manipulator can be shifted to the
work area (6) of the manipulator such that those objects (d) which can
reach said work area (6) when the manipulator starts to perform the
collection will also be taken into account when performing the
calculations of the positioning times.

[0030] In other realizations the collecting area can comprise a different
number of products or even a single product. The containers (3, 4) can
also comprise a different number of empty housings (for example 4, 6
etc). Only two rest positions (1,2) for the containers (3, 4) have been
shown in the figures, but these rest positions can comprise a third or
more rest positions.

[0031] The method comprises the following phases:

[0032] 1--Calculating an available time td corresponding to the time
necessary for an empty housing (31, 32, 41, 42) of a container (3, 4) to
reach a loading position (11, 12, 21, 22),

[0033] 2--Calculating for each of the mentioned at least one object (a, b,
c, d): [0034] a) a positioning time tp11 necessary for the manipulator
to reach a first loading position (11) coinciding with the position of a
first empty housing (31, 41) of a container (3, 4). The positioning times
tp11a, tp11b, tp11c and tp11d would be obtained [0035] b) a positioning
time tp12 necessary for the manipulator to reach a second loading
position (12) coinciding with the position of a second empty housing (32,
42) of a container (3, 4). The positioning times tp12a, tp12b, tp12c and
tp12d would be obtained [0036] c) a positioning time tp21 necessary for
the manipulator to reach a third loading position (21) coinciding with
the position of a first empty housing (31, 41) of a container (3, 4). The
positioning times tp21a, tp21b, p21c and tp21d would be obtained [0037]
d) a positioning time tp22 necessary for the manipulator to reach a
fourth loading position (22) coinciding with the position of a second
empty housing (32, 42) of a container (3, 4). The positioning times
tp22a, tp22b, tp22c and tp22d would be obtained

[0038] 3--Comparing the available time td with the positioning times
tp11a, tp12a, tp21a, tp22a tp11b, tp12b, tp21b, tp22b tp11c, tp12c,
tp21c, tp22c tp11d, tp12d, tp21d, tp22d to determine a loading position
(11, 12, 21, 22) of the manipulator and an object to be loaded (a, b, c,
d) the positioning time of which is closest to the available time td. In
other words, it decides which of the objects (a, b, c, d) is going to be
collected and in which housing the object will be loaded in.

[0040] In a first embodiment the available time td, and the positioning
times tp11, tp12, tp21 and tp22, of each object (a, b, c, d) can be
calculated from the detection of the start of the movement of the
containers (3, 4) between a first rest position (1) and the at least one
second rest position (2). This case is applicable, for example, when an
operator can force the start of the advance of the machine, or when it is
difficult to accurately establish the performance of the advance of the
machine and the products that must be loaded in the rest positions.

[0041] In this embodiment, while the machine advances, the manipulator
introduces the products in the different empty housings, loading the
products with the containers stopped, but, for example, the advance of
the container can be started when the manipulator has finished loading
one of the two housings of a container and the second housing is starting
to be filled. Unlike in the state of the art, at the time that the
manipulator detects that the advance of the machine (and accordingly of
the containers) occurs, it will recalculate the delivery position and go
directly to the corresponding empty housing, without tracking the housing
it was trying to load. Likewise, if the advance of the machine occurs
when the manipulator is going to collect an object (a, b, c, d), the
positioning times tp11, tp12, tp21, tp22 of all the objects which at the
time of collection are in the work area (6) will be recalculated, and the
object to be collected and the loading position in which to deposit it
are determined depending on which of all the positioning times tp11a,
tp12a, tp21a, tp22a tp11b, tp12b, tp21b, tp22b tp11c, tp12c, tp21c, tp22c
tp11d, tp12d, tp21d, tp22d is most similar to the available time td.

[0042] Assume, for example, that the manipulator collects an object to be
loaded and starts the movement towards a target loading position (11, 12,
21, 22), corresponding to an empty housing (31, 41, 32, 42) of a
container (3, 4). In this embodiment, when the start of the advance of
the machine is detected, the new positioning times tp11, tp12, tp21 and
tp22 are calculated taking into account the current position of the
manipulator, and the loading position (11, 12, 21, 22) is recalculated
comparing said positioning times tp11, tp12, tp21 and tp22 with the time
that the containers will need to reach the rest positions (the available
time td to end the advance of the machine). Based on this calculation it
decides whether to maintain the target loading position, perform the
delivery of the product in a new loading position, or whether to choose
another loading position considering distance criteria regarding the
radius of action of the manipulator, complete the filling of all the
housings, or others.

[0043] In this case, the manipulator can choose to not vary its path,
performing the delivery in the same loading position (11, 12, 21, 22) as
before the advance of the machine, and deposit the product in a new empty
housing which will take the place of the empty housing which has advanced
to a second rest position; it can also vary its path and got to a new
loading position which corresponds with the new position which the target
empty housing will occupy, once the advance of the machine has ended
(going directly to the final position of said housing without tracking
the same during the advance); or it can choose to perform the delivery of
the object in a loading position in which any other empty housing is
located, in which case it will also go directly to the final loading
position, instead of tracking or making a curved path during the advance
of the machine.

[0044] Keeping with the previous example, in the event that when the
advance of the machine is detected the positioning time most similar to
the available time td corresponds with the time necessary for reaching
the same target loading position before starting the advance movement,
the housing in which the delivery was to be performed before the advance
will continue to be empty in a second loading position, since the product
will be deposited in the empty housing of another container which will
reach the target position after the advance of the machine. Likewise, if
when the advance of the machine is detected the available time td
corresponds with the time the manipulator needs to reach from its current
position the new position which the target housing will occupy after the
advance of the machine, the manipulator will go directly to the new
loading position (without tracking the housing). By the same logic, it
can also occur that the new target housing is different from any of those
explained above, or even that other loading criteria which can be
combined with the method of the present invention take precedence, such
as for example completing the filling of all the housings before they
leave the work area (6) of the manipulator, distance criteria with
respect to the radius of action of the manipulator, or others.

[0045] When in the case of the previous example the advance movement of
the machine is detected without the manipulator having any object to be
loaded, the positioning time of all the objects (a, b, c, d) that may be
within the collecting area (5) comprised in the work area (6) of the
manipulator in the moment of the collection will be calculated. In other
words, those objects which, though outside the work area of the
manipulator at the precise moment of detecting the advance of the
machine, may be shifted to the collecting area (5) during the time the
manipulator needs to reach from its current position to the position of
the object in said collecting area, and the positioning times of each
object in each housing will be compared with the available time td for
collecting the object (a, b, c, d) the positioning time tp11, tp12, tp21,
tp22 of which in a determined loading position (11, 12, 21, 22) is the
closest to the available time td. As in the previous example, in this
case can also take precedence other criteria such as the priority in the
collection (i.e., prioritize the collection of those objects which are
going to leave the work area of the manipulator) when choosing the object
to be loaded, or others.

[0046] According to the method, the machine already knows beforehand were
the empty housings are located once the advance (both those of the
container having all the empty housings, and those which it left to load
in another container) ends, it can also estimate the time during which
the advance of the machine to occurs and is able to foresee in which
collection positions the objects to be loaded are located over time.
Therefore, it will calculate the positioning time tp11, tp12, tp21 and
tp22 that the manipulator would take to load each of the objects (a, b,
c, d), carrying them directly (taking a rectilinear path seen from above)
to each of the loading positions which will correspond to the empty
housings of the containers once the advance has ended, and the object to
be loaded and the new loading position will be that the positioning time
of which is the most similar to the advance time of the machine, which in
this case coincides with the available time (unlike in the state of the
art, in which the manipulator follows the movement of the housings).

[0047] As a result, the method of the invention optimizes productivity of
the manipulator since it prevents the excess time necessary for tracking
the paths during the advance of the machine.

[0048] In a second embodiment, the available time td can be calculated as
the sum of the advance time ta and a remaining time trem for the
movement of the containers between a first rest position (1) and at least
one second rest position (2) to start.

[0049] In this case, product assignment is optimized based on the
knowledge that is available with respect to the advance cycle of the
machine.

[0050] When choosing the object (a, b, c, d) to be collected and
determining its loading position, the remaining time trem is
calculated before the start of the movement of the containers and which
objects are to be loaded and the loading positions the positioning time
of which is less than the time it takes for the advance to start
trem are determined. For example, when the remaining time trem
is greater than any of the positioning times tp11, tp12, tp21, tp22, the
object to be collected and the delivery position corresponding to the
positioning time that is closest to the remaining time trem are
determined, although as in the previous case, other loading criteria
which can be combined with the method of the present invention can also
take precedence, such as for example completing the filling of all the
housings before they leave the work area (6) of the manipulator, distance
criteria with respect to the radius of action of the manipulator, or
others.

[0051] In the event that the remaining time trem is less than said
positioning times, the calculation is repeated, but taking into
consideration the available time after the advance of the containers,
i.e., the advance time ta plus the remaining time trem,
ta+trem.

[0052] Finally, the object (a, b, c, d) to be collected and its optimal
destination housing are determined by comparing the positioning time
tp11, tp12, tp21, tp22 that most closely resembles the available time td,
or considering a distance criterion with respect to the radius of action,
completing the filling of all the housings, prioritizing the collection
of those objects leaving the work area (6) of the manipulator, or others.

[0053] In principle, according to this method, it would not be necessary
to apply the method of the first embodiment, but cases are possible (due
to the difficulty of accurately establishing the performance of the
advance of the receptacle) in which the combination of both improves the
final result.

[0054] The method of the second embodiment differs from the first
embodiment in that it is predictive: in the previous case, the
manipulator recalculated the loading positions when it detected the
advance movement of the machine. In contrast, in this second method, the
manipulator will know at all times when the advance of the machine will
occur, and depending on the time it has (before or after the advance) it
will decide where to deposit the product.

[0055] In this case, in the moment in which the manipulator deposits a
product in a housing and is going to collect a new product from the
collecting area (5), it calculates the time it has for the advance of the
machine to occur trem and the available time it has for the advance
of the machine to end trem+ta. It can thus decide which product (a,
b, c, d) to collect and in which position to deposit said product,
depending on the time it has before the advance, the time it has from
that moment to after the advance, or other criteria.

[0056] For example, it will choose to collect an object and deposit it in
a loading position in the first rest position (1) if there are no
housings that will be out of reach of the manipulator once the machine
advances or if the remaining time trem is the most similar to the
time it takes the manipulator to collect said object and reach the
loading position in the first rest position (1).

[0057] The manipulator will choose to collect an object and deposit it in
a loading position in the second rest position (2), i.e., the housing in
the second rest position after the advance of the container, if the
available time at which the advance of the machine ends trem+ta is
the most similar to the time it takes the manipulator to collect said
object and directly reach the loading position in the second rest
position (2).

[0058] In a third embodiment, the loading position corresponds to a
position of an empty housing between the first rest position (1) and the
second rest position (2), i.e., the manipulator can perform the loading
during the movement of the container without it being necessary to wait
to be in a rest position.

[0059] According to this third embodiment, the available time td is
calculated as the sum of the advance time to and a remaining time
trem for the movement of the containers between the first rest
position (1) and the at least one second rest position (2) to start, the
available time td being greater than the positioning times tp11, tp12,
tp21 and tp22 of each of the objects (a, b, c, d) in the different empty
housings of the containers, and the remaining time trem less than
the positioning time tp11, tp12, tp21, tp22, i.e., when the manipulator
does not have time to collect and load the object before it starts the
advance of the containers but this time is less than the available time
for the containers to reach the second rest position. In this case, the
manipulator will collect an object and deposit it in a loading position
corresponding with an empty housing moving from the first rest position
to the second rest position.

[0060] This implies that there is communication between the manipulator
and the packaging machine, such that the manipulator knows at all times
the time it has until the advance, how long the advance will last and
exactly where the empty housings will be located throughout the advance
process, such that it is possible for it to calculate which object to
collect and the best loading position for loading said object which
optimizes the performance of the machine-manipulator assembly at all
times.

[0061] The delivery of the object in the loading position is performed
with a substantially nil relative velocity with respect to the container
and a shifting direction substantially parallel to the advance direction
of the container. The manipulator knows the position of the housing at
all times and goes towards a loading position in which it will find the
corresponding housing. Once the manipulator is in the vicinity of the
loading position, it adapts its velocity and direction such that they
substantially coincide with that of the housing in order for the delivery
of the product to be performed in the best conditions.

[0062] It must be pointed out that the invention is not limited to the
product filling field, but rather it is also applicable in any other
process performed by manipulators acting on a product which moves
intermittently at a variable velocity (welding, palletizing,
manipulation, unloading, product selection processes, etc.).